Attachment and wall plug



31, 1938. w. c. MORFORD ATTACHMENT AND WALL PLUG Filed Nov. 14, 1953 QM/LKMK Patented May 31, 1938 STMES 3 Claims.

This invention relates to improvements in attachment and wall plugs and has for its object to provide a simple, efilcient and inexpensive device of this character.

One of the objects of this invention is to provide an attachment plug the sections of which may be more quickly and conveniently intersecured one upon the other.

Another object of this invention is to provide an attachment or wall plug with a male and female section so shaped, designed and constructed as to permit ready insertion of one section into the other with a minimum of time and exertion whereby a true electrical contact may be maintained between both sections at all times.

A further object of the present invention is to provide an attachment plug of two sections designed to be interengaged detachably in such a manner that a good electrical contact is made immediately when thetwo sections are secured one upon the other.

A still further object of this invention is to provide an attachment or wall plug with means for quickly securing the electrical wires upon the male section and efficiently without the hazard of the wires becoming shirred accidentally.

Another important object of this invention is to provide an attachment plug with a more rapid manner of assuring that the two sections may be interengaged electrically than is true of conventional plugs due to the circumstance that the construction of the interfitting parts of both sections is such that even in the dark they may be interconnected without a hit-and-miss repeated trial effort.

A final object of this invention is to provide an attachment plug of a male and female section where the female section has a central bore and counterbore while the male section has a central rod with a forwardly projecting pin for respective insertion into the counterbore and bore of the female section, there being no loose contact members in the female part or in the male part of the attachment plug likely to cause trouble due to short-circuiting.

With the above and other objects in view my invention consists in the combination, arrangement and details of construction disclosed in the drawing and specification, and then more particularly pointed out in the appended claims.

In the drawing, in which similar reference characters designate similar parts throughout the respective views,

Figure 1 is a vertical sectional elevation of my invention,

Figure 2 is a top plan view of the female plug section,

Figure 3 is a bottom plan View of the female plug section,

Figure 4 is a bottom plan view of the male sec- 5 tion of the invention,

Figure-5 is a front view of the female section,

Figure 6 is a top plan view of the male section,

Figure 7 is a side elevation, partly broken away of the male section to a different scale than Figure 1,

Figure 8 is a side elevation of the male section, on a still different scale,

Figure 9 is a longitudinal section taken through a portion of the male section showing how the same is cut away for receiving the electrical con tact members.

Referring to the drawing, which is merely illustrative of my invention the various parts are now detailed. The attachment plug consists of a male section 22, and a female section Hi. This female section consists of a porcelain or insulator body tapering as at H at one end, and it is formed peripherally with a series of threads upon which is screwed a brass collar !2. The body, towards its opposite end flares as at 83, which has a transverse flat portion is see Figure 5 upon diametrically opposite points of which are located notches or recesses l5.

The female section it is formed with a central bore I6 and with a counterbore extension thereof designated I i. A contact post or rod l 8 fits snugly and projects partially into the outer end of the bore I6, and has a tapered tip end projecting beyond the tapered portion l i of the body ll]. There is a contact member 20 which extends transversely into the interior of the insulator body Ill.

The inner end of the contact member 2!] curves slightly downwardly into the counterbore ll, 4 while its outer end may be secured as by means of solder Z! to the brassthreaded collar l2.

The male section may also be made of porcelain and of non-metallic material, and it consists of the forwardly projecting integral cylindrical rod 23 formed with a reduced stem or cylindrical pin 24, so that an annular shoulder exists between the outer end of the rod and the inner end of the integral pin thereon. Also centrally disposed in the male body 22, which has an inner part extending transversely as a flat portion and an outer part formed convex, is a socket 26 extending along the axis of the male section. The inner end of this socket 26 communicates by means of the oppositely-arranged and diametrically opposed vertical slots M and N with diametrically opposite notches or recesses 21 formed so as to open out of the inner fiat portion of the section 22, these notches flanking the base of the rod which, at this point, is formed integrally upon the male plug section.

Arranged in concealed relation centrally of the rod 23 and the pin 24 is a contact strip 28 whose lower angular portion or terminal 29 extends laterally outside the rod and extends into the recess 21 on one side of the rod. There is a collector ring 36 embracing the pin 24 and seated on the annular shoulder formed by this rod with the pin, this ring having the same outside diameter as the rod itself. There is another contact strip 30 countersunk into the peripheral surface of the rod 23, and having its upper end electrically connected to the collector ring 35, while its lower angular terminal extends laterally of the rod 23 and projects into the other notch or recess 21. It will be seen from Figure 9 that there is a center passage 32 made to receive contact member 28 so that the angular passage ofiset 31 will receive the angular ofiset 29 of this contact member. Similarly the groove 33 formed upon the side of the rod 23 receives the contact member 30.

A flexible cord consisting of the parts A and B enters the bore 26 of the male section 22 and carries the opposing shirred wires 34, which extend in opposing directions so that the wires may have flat contact with the under sides of the contact member terminals 29 and 3| respectively, so that now the binding screws 35 may be screwed home tightly to clamp the wires against the terminals 29 and 3| in the notches 21. In this manner the wires are concealed from view and cannot become easily frayed or abused so as to cause any short connection or short circuit condition at all.

It will be seen that since the rod 23 is of a slightly larger diameter with respect to the pin 24, that the pin will quickly enter the counterbore ll of the female section II], loosely, and once it so enters it will enable the rod 23 to quickly enter the counterbore and now the operator does not have to be careful to assure that the contact will be made, as in any circular position in which the rod and pin maybe disposed in their respective counterbore and bore of the female section [0, electrical contact will be made. The contact strip 28 will contact the contact member l3, while the contact member 20 of the female section will engage the collector ring 36 in any points of its peripheral circumference, and since there is a good electrical connection made in the recesses 21 between the terminals of the contact strips which supply current to contact rod 18 and collector ring 36, a positive action is made for the abutting contact members.

When the male section is forcibly detached from the female section the electrical contacts are broken and the circuit is disrupted. It will be seen that spring clips H have base portions secured by the fasteners K to the male section 22, these clips being curvilinear portions that will snap automatically into the annular groove or opposing notches I5 formed upon the female section ID to assure that the flat inner parts of both sections are in firm contact. I do not confine myself to the exact details of construction herein disclosed but cover all variations falling within the purview of the appended claims.

What I desire to claim and seek by Letters Patent is:

1. An attachment plug consisting of a female and a male plug section of insulating material, a threaded metal collar carried externally by said female section, the latter having a cylindrical bore, a contact rod in said bore having a tip plugging one end of the female section, the male section having a forwardly projecting cylindrical rod designed to snugly enter said bore, a contact strip embedded in said rod and designed to abut the contact rod, a collector ring fitted circumferentially around said rod, a contact member embedded in the female section abutted by the collector ring when the rod is in the bore, said contact member being soldered onto the threaded collar, and means located in the male section for conducting current to said collector ring and to the contact strip in said rod.

2. An attachment plug consisting of a female and a male insulator plug section, the female section having a brass threaded collar enclosing same externally and having a central bore, a contact rod in said bore, a contact member soldered at one end to said collar and penetrating the female section to provide a contact member, the male section having a rod projecting therefrom, a collector ring carried by said rod for engagement with said contact member electrically, means detachably securing the male section upon the female section and for seating the rod in the bore of the female section, a contact member embedded in said last-named rod designed to engage the contact rod of the female section, a flexible cord projecting into the male section and having electrical wires, and means in the male section whereby the electrical wires from said cord are caused to convey current to the collector ring and to the contact member.

3. As a new article of manufacture a male atits innermost part.

WALTER C. MORFORDP 

